Petrogenesis of a Late Carboniferous mafic dike–granitoid association in the western Tianshan: Response to the geodynamics of oceanic subduction

Petrogenesis and geodynamic implications of the Late Carboniferous felsic volcanics in the Bogda belt, Chinese Northern Tianshan

“…The calculated zircon saturation temperatures (T Zr = 792-842°C) were also in the overlapped field of typical A-type and I-type granitoids (King et al, 1997;Zhong and Xu, 2009;Liu et al, 2013). In fact, the Late Carboniferous felsic rocks in the Chinese Tianshan Orogenic Belts often belong to I-type (Zhu et al, 2009;Tang et al, 2010;Tong et al, 2010;Liu et al, 2013;Tang et al, 2014;Zhang et al, 2015), whereas the Early Permian felsic rocks are mainly A-type granitoids (Tang et al, 2010;Yuan et al, 2010;Zhang and Zou, 2013;N.-B. Li et al, 2015).…”

High-alumina basalts from the Bogda Mountains suggest an arc setting for Chinese Northern Tianshan during the Late Carboniferous

“…In addition, they have restricted zircon saturation temperature (T Zr = 792-842°C) in the overlapping region of the typical A-type granite and I-type granite (King et al, 1997;Liu et al, 2013;Zhong and Xu, 2009). In fact, most of Late Carboniferous felsic rocks in the Chinese Tianshan Orogenic Belts belong to I-type granitoids (Liu et al, 2013;Tang et al, 2010Tang et al, , 2014Tong et al, 2010;Yan et al, 2013;Zhang et al, 2015;Zhu et al, 2009). In contrast, A-type granitoids mainly occurred in the Early Permian (N.-B.…”

Petrology and geochemistry of late Carboniferous hornblende gabbro from the Awulale Mountains, western Tianshan (NW China): Implication for an arc–nascent back-arc environment

“…Additionally, mafic dike-granitoid associations are common in extensional tectonic regimes (Yang et al, 2007;Xu et al, 2008;Said and Kerrich, 2010). The late Carboniferous mafic dike-granitoid associations reported by Tang et al (2014) and Liu et al (2012) outcrop in the Muhanbasitao and Zhongyangchang area of the Awulale Mountains, respectively. The subduction-related signatures of these associations indicate that they are not related to a post-collisional extensional setting and a back-arc extensional setting would be a suitable environment for their emplacement.…”

“…10b), reflecting a somewhat heterogeneous mantle source. These geochemical characteristics of the Wuling gabbro resemble the features of the 314 Ma Fe-rich basalts (( 87 Sr/ 86 Sr) i = 0.7046-0.7058, e Nd (t) = 3.0-4.7, T DM 2 = 0.9-1.4 Ga) in the Chagangnuoer area (Li et al, 2015b) and the 310 Ma mafic dike (hornblende gabbro) (( 87 Sr/ 86 Sr) i = 0.7048-0.7053, e Nd (t) = 2.9-3.8) in the Zhongyangchang area (Tang et al, 2014) and the 317 Ma hornblende gabbro in the Muhanbasitao area (Liu et al, 2012) (Fig. 10a), all of which have been considered to form in an active continental margin environment.…”